The goal of this game is to get 3 in a row of your colour and it also has to be 3 in a row of paper rock or scissors.
Rock beats scissors. Scissors beats paper. Paper beats rock. There is also a bomb and an undo card. The undo card can undo any card except another undo card. The bomb card can not be beaten by anything other than another bomb. What the Bomb card does is you put it on a card; then only a bomb can go there until it's the turn of whoever played the bomb card. The bomb (and all the cards under it) go away. Then, the player who played the bomb card can put their card there because the bomb will not be there anymore.
Here is a helpful tip with the bomb: Say you have 2 papers in a row but the spot where you need to put that other paper already has a scissor card so you can't play paper on it, but you can play a bomb card there. Then the other player needs to choose a spot to put their card. If it's not a bomb, nothing goes on the bomb card. When it's your turn the spot where the bomb card was will go away leaving it open. Then since it's open, any card can go there so put the paper card there and then you win the game!